Abstract: An integrated computer, scanner, and printer has elements of all three in a single enclosure with a single CPU performing all of the control tasks for the three, usually separate, devices. The three functions also share memory space, and control circuitry for the scanning and printing operations are interfaced directly to the system bus of the computer. Control routines in a preferred embodiment are integrated into a single system BIOS. In embodiments of the invention, a light source, such as a laser source, used for electrostatically writing images on a drum for printing, is diverted and also used for scanning operations. In another alternative embodiment, a device-driver-software transparent extended enhanced parallel port is provided for expansion of the bus into an external copy of the internal bus, such that expansion ports may be transparently provided in an external docking box.